The invention relates to the field of the cosmetic industry.
Perfumes, after-shave products, toilet waters, deodorants and, in a general way, all perfumed cosmetic compositions are, for the most part, made up of an ethanolic solution of some titer, most often 90xc2x0, containing aromatic preparations which have been refined to a greater or lesser degree.
Ethanol is traditionally used in cosmetics"" compositions as a dissolving agent since it offers numerous advantages. It is liquid under normal conditions of pressure and temperature. It permits the dissolution of natural or synthetic aromatic compositions. It does not interact or does so only very slightly with the dissolved molecules. It evaporates rapidly on contact with the skin.
Furthermore, ethanol is a solvent with very low toxicity with respect to the quantities used under normal usage of such cosmetic compositions.
To the knowledge of the applicant, at the present time, other solvents do not exist which could substitute for ethanol in such compositions.
Within the context of cosmetic compositions, the use of ethanol nevertheless does have a certain number of disadvantages.
Since the use of ethanol is prohibited in certain countries, notably Moslem countries, the use of perfumed compositions containing it is also prohibited.
Another disadvantage of ethanol stems from the stinging sensation associated with its use.
Finally, it should be noted that ethanol can also cause drying of the skin and the appearance of red blotches.
The main objective of this invention is to propose a range of compounds capable of being used as dissolving agents in cosmetic compositions, replacing the ethanol.
This objective is achieved thanks to the invention which relates to a cosmetic composition comprising at least one aromatic compound and at least one dissolving agent for said aromatic compound characterized in that said dissolving agent is a perfluorinated hydrofluoro ether.
Therefore the invention proposes to replace ethanol by a perfluorinated hydrofluoro ether in the cosmetic compositions.
Such fluorinated solvents offer crucial advantages when compared with ethanol.
In the first place, perfluorinated hydrofluoro ethers are non-toxic and cause neither red blotches nor any stinging sensation.
Furthermore, the use of hydrofluoro ethers is not subject to any regulation.
In addition, these fluorinated solvents are of interest because they are chemically inert and are not able to react with any of the usual constituents of cosmetic formulations. They are volatile compounds which, after evaporation leave no trace whatsoever.
These fluorinated solvents are also of interest in not being subject to any regulation whatsoever and can therefore be universally used.
The fluorinated compounds proposed by the invention are, in addition, without odor or color. They can therefore be integrated into cosmetic formulations without the risk of masking the perfumes or harming the fragrance of the product or modifying its appearance.
In addition, the hydrofluoro ethers have a lower boiling point than ethanol and above all, very low heat capacity and latent heat of vaporization which permits rapid evaporation without trace. These physical and chemical properties increase the feeling of freshness felt when the perfumed composition is applied.
Finally they present no risk for the ecosystem and conform to the most strict environmental regulations (potential for destroying the ozone layer xe2x80x9cODPxe2x80x9d zero and contribution to the greenhouse effect xe2x80x9cGWPxe2x80x9d very slight).
It should also be noted that the fluorinated solvents proposed by the invention are safer than ethanol since they are non-inflammable and do not have a flash point.
According to a preferred variant, said hydrofluoro ether has a total number of carbon atoms that is greater than or equal to 5 and is made up of a perfluoro alkane chain, branched or not, cyclized or not and aromatic or not, bound to an alkoxy group, said alkoxy group having between 1 and 7 carbon atoms, said hydrofluoro ether having a boiling point at atmospheric pressure of between +15xc2x0 C. and +100xc2x0 C.
Also, preferably, said alkoxy group of said fluoro ether has between 1 and 5 carbon atoms.
Advantageously, said hydrofluoro ether has a boiling point at atmospheric pressure of between +30xc2x0 C. and +80xc2x0 C.
In the most preferred way, said hydrofluoro ether is chosen from the group made up of methoxy-nonafluorobutane (C4F9OCH3) and its isomer ((CF3)2CFCF2OCH3), ethoxy-nonafluorobutane (C4F9OC2H5) and its isomer ((CF3)2CFCF2OC2H5), and propoxy-undecafluoropentane (C5F11OC3H7).
It should also be noted that the composition according to the invention may include at least one co-solvent, preferably chosen from the group made up of ethanol and water. By co-solvent, one understands any molecule of such a chemical nature that may be added in variable quantity to the hydrofluoro ethers for the purpose of modifying the properties of the composition thereby obtained.
Advantageously, said aromatic compound incorporated into the composition according to the invention is chosen from the groups made up of the essential oils, natural and synthetic fragrances and the resin oils.
According to the invention, the natural or synthetic aromatic compounds can be simply diluted in the hydrofluoro ether or hydrofluoro ethers. The proportions of one or other of the constituents is not important since the hydrofluoro ethers have a high solvent power, associated with their ether group, that allows complete dissolution of aromatic compositions.